db_config and other questions

["Jonathan Higgins" <jhiggins@kennesaw.edu>]

im database illiterate.. so 
1. Should I define the environment variable DB_HOME in my LDAP start up script or is there somewhere else that it needs to be defined?
2. Once ive got the DB_HOME set, does openldap-2.1.21 know to look for this environment variable or do I need to tell it about it?
3.  What are some optimal settings that should be placed into the DB_CONFIG file to maximize read only performance.
4.  Should I worry about setting bdb options inside slapd.conf if they are already specified in DB_CONFIG?

other questions:
Im upgrading 2.0.25 to 2.1.21 .. I planned to build a stable 2.1.21 and load it with some data, and test my build.
1. Will I be able to replicate any changes from 2.0 to 2.1? 
2. How would I specify only specific updates instead of all changes replicating.

lastly..
In the simplest terms, could someone explain the rootDSE.

Thanks all



Jonathan Higgins
Network Service Specialist IV
Kennesaw State University
jhiggins@kennesaw.edu

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